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Topic: Aluminized Steel Plate (Read 10770 times)

I've posted about this plate previously but I have new information. I really would like to hear from somebody else who has experience with them and truly wonder if these are not a solution to a problem. The plate in question is here....

Here's the story. I have a 1/2 size Cadco convection oven in 220 volt and steam injection in my kitchen for baking bread. I started using it for Pizza two years ago and have had excellent results. While vacationing at the beach the month of November (North Florida, its beautiful), I tried this plate in a cheap electric oven and found that it heated to over 460 deg. F on the top rack in the time it took to oven to heat and the light to go out. This is as hot as it ever got in my convection oven. I tossed the pizza onto the plate, with a cardboard peel from a pizza box, turned on the broiler and... Bam, Pizza (yes, I stole that).

The pizza was better baked than any I tried in the area, and featured in Pizza Today in a Florida Panhandle article. The month of November saved, I tried the plate in my high-end home oven (DCS with salamander broiler) and damn if it didn't heat to 500 deg F in the time it took the pre-heat light to go out. Tried the same broiler trick and... Bam, even better pizza. The bake was beautiful, lasting crispy bottom and top, some charring on top...real charring not just blackening from the salamander type broiler. The bottom, while not charred, was really done to a lasting cripness, I think I can improve this even further maybe to char with the right tweaks and dough.

Now, I'm limited to a 12 inch pizza because of the size of the plate (1/2 size) but I'm diabetic so this is all my pancreas can handle anyway but a full size plate could be cut down to fit a standard oven and allow larger sizes. Aluminized steel has unique properties, as stated in a wikipedia article it's "a material with a unique combination of properties possessed neither by steel nor by aluminum alone". I feel it may address the problems of the steel plates tried on this site. I'm not a materials scientist, someone here may be, so I can't exactly explain my findings. These things heat fast and hot, even in still air (no convection) and deliver the heat out the top into the pizza and recoup it from the bottom, real fast. They stay hot, after removing the first pizza they are back to full heat in a minute or so, really.

My next pizza excursion will include full photos, pizza porn if you will, but I would like to start a discussion now if anybody can explain aluminized steel and what those unique properties are, besides really good pizza.

scott123

Aluminized steel shows a better behavior against corrosion[1] and keeps the properties of the base material steel for temperature lower than 800°C (1,472 F).

The aluminum is too thin to alter it's baking properties. It's just there to prevent corrosion. This is why aluminized steel deck ovens can last for half a century. Since almost all home bakers have no issues with corrosion, the aluminized aspect is somewhat trivial. For baking pizza at home, an aluminized plate and a non aluminized plate will produce identical results.

The amazon page lists the thickness as .2" which is pretty much 3/16". Steel and iron have very similar baking properties. In our recent discussion here,

In other words, you're essentially using a cast iron pizza pan analog. If you read the reviews on Amazon, it is much loved. As Craig pointed out in that thread, though, your average Amazon reviewer may not be as obsessive as we are.

As far as bottom browning goes, neither

This Broil King plate3/16" steel plateCast iron pizza pan

will bake a pizza in much less than 7 minutes in a typical home oven.

There's absolutely nothing wrong with making the decision that crispy bottomed pizza is your thing and to never strive for anything else (like Mistachy is doing with his 3/16" steel plate purchase), but for those less certain, I highly recommend a material that will give a wider range of bake times (down to 4 minutes) and that's thicker steel plate.

Or stacking- which we've already discussed in depth and needs further testing to be viable.

The plates... Notice that bakes times are stated at 5 to 7 minutes, my experience is 3 1/2 to 4 1/2 if two plates are used in the convection oven (one over and one under), or, pizza directly on plate with broiler turned on at launch in conventional oven (no convection or with convection). The manufacturer further states that the plates are constructed of material that provides superior heat storage and cook both top and bottom of pizza simultaneously. My experiences bear this out. I was doing this with these plates before their ovens were specifically designed for pizzas.

Note that I state that the plates can reach 500 degrees in only the time it takes to preheat a conventional electric or gas oven to that same setting. I notice that people using steel plates are preheating a much longer period of time. This may be due to the relative thinness of the plate, the black nonstick coating or the material used in its construction, or maybe a combination of all three. The time it takes to recoup heat after baking a pizza is only a minute or so and the next one can be launched.

I see people here flailing about with massive steel plates, reinforcing oven racks and getting hernias, when a device is specifically designed to do just what they are attempting that you can lift with one hand (well, its slippery and a bit of a stretch but I could do it). I think that until somebody else has tried one of these plates nobody is going to take me seriously.

What information can I provide that will be considered seriously? These plates work. Would you like to design a series of tests that I can perform to provide unbiased data. I have: a Cadco convection oven 1/2 size 220 volt, a gas high end home oven with a convection fan on its own switch, an infrared thermometer, advanced photographic skills, time (I'm retired), basic pizza skills and a true desire to help other pizza makers. Currently I have one aluminized steel plate and another aluminum plate of older design, I plan on getting another aluminized plate soon. I'm really serious too.

I gave up on stones a long time ago after trying several, gave them away. I don't think any oven you want in your home has the horsepower to run them properly, the thermodynamics are just wrong. I started using convection oven plates before the aluminized steel one was available and got much better results.

Your link to the pizzas is awesome, I'll be taking some temperature readings and baking some pizzas in a few days using my conventional oven, which I have just started using the plate in. I use a New York style Lehmann dough so charring on the bottom won't really be possible. I plan on working on a Neapolitan dough in the near future where I'll be looking for some charring, totally believe its feasable based on my Lehman dough results in the gas oven. I assume the resistance to my discovery lies in the lack of charring on the bottom, but I'm using high-glutgen pizza flour and a 60% hydration which I think is retarding the char. My bake times are definitely in the neighborhood of Neapolitan.

What are we referring to when talking "stacking"? a stack of steel plates, corderite on top of steel, steel on top of corderite? Don't see any advantgage to that if I'm correct.

What are we referring to when talking "stacking"? a stack of steel plates, corderite on top of steel, steel on top of corderite? Don't see any advantgage to that if I'm correct.

Ron

Ron, another user, whose name escapes me, had marked success using a cast iron pizza pan on top of a cordeirite stone. How it seemed to work (best guess) was that the stone served as a thermal reservoir, and the conductive metal served as a delivery medium. Two materials, using their strengths to cancel each other's drawbacks to reach new heights.

Sounds like an interesting theory, (we all have them don't we). My theory is that the black Teflon and aluminum coated steel plate quickly replaces the heat driven into the pizza from infrared and convection (ovens all convect to some degree whether they are convection ovens or not) available in the oven.

Thanks for the explanation, I think it may actually be a version of what my plate is. If aluminized steel was used strictly for its corrosion resistance then an aluminum plate would be superior to the aluminized steel, lighter, cheaper and just as effective. I feel the steel acts as a heat sink powering the aluminum which picks up and delivers the heat more efficiently than the steel can. In the case of the stack, its a combination of materials and may well be making up for each others deficiencies.

Remember, these plates are commercially designed to produce pizzas in a commercial environment. I often adapt commercial recipes, techniques and equipment into my home kitchen whenever I can, and am never dissapointed. I'm sitting at a meat cutting table as I type this, its cutting board, high hat style dinner table, buffet for guests and all round go to table in the house. My wife is very tolerant of me.

Actually, aluminizing steel makes it reflect more heat. According to what I have found 80% of the heat thrown at it is reflects away, that seems like a bad thing for pizza making IMHO....but you cannot argue results.

Like others I am curious to see your results. That said I do not think you will have luck with Neapolitan. I've got lots of experience under my belt cooking neapolitan on steel that I'm not going to go into too much detail about, but I would bet with your thermal mass you will need the plate at least 700F for a neapolitan bake. 3 1/2 minutes with a malted flour is an ocean away from 60 seconds with un malted flour and even then getting the top cooked in 60 seconds is even harder then getting the bottom there.

Did preliminary test of aluminized plate in gas oven tonight. I still have tweaking to do. Plate registered 520 degrees at end of oven preheat, I opened the dough while preheating and topped when the light went out and launched. I did not use the broiler for the top bake this time and that reduced top leoparding, but I am still working things out.

I did some quick reading on how Aluminized steel is made, and as Scott mentioned it's simply a steel plate with a thin aluminum coating.

HOWEVER

I'm wondering if the thin aluminum coating may actually "turbocharge" the conductivity of the steel plate, in essance making it a super-conductive steel? I imagine there must be some type of increase in heat-transfer due to the aluminum layer "pulling" heat from the steel much faster than a pizza on just plain steel.

I'm thinking along similar lines of how copper-bottom pans work, if anyone knows what I'm referring to?

The bake time on this pizza was about 6 minutes and was a Lehmann style dough made with commercial pizza flour, now, I can do it faster if I use the broiler and my oven has a little more punch than I used last night but, remember, this pan heated to 520 degrees in only the time it took the oven to preheat, without convection. The heat absorption of this material is incredible and while the pizza is baking on the top its recouping heat from the bottom. Nobody here seems to understand this material or have any experience with it. Aluminized steel was chosen by Cadco for this exact use, to bake a pizza. Previously they sold a plate of pure aluminum (with teflon like material on top) that had projections from the bottom to increase surface area, I have one and it was called the Fakiro plate and cost twice as much. The Fakiro does not work as well, almost, but not quite, it cools more after a bake than the aluminized steel, it doesn't pick up as much heat during the bake but does heat as quickly in the preheat.

My assertion is that the aluminized steel does preheat and discharge heat far more efficiently than carbon steel and surely more than stainless. I was hoping somebody understood the material better than I and could give us more information so I could optimize its use. This plate is designed for a convection oven that maxes at 500 degrees, I've used it in one of their ovens extensively for New York Style before realizing it may be interesting to try in my gas oven. It actually performs better in the gas oven than in the convection oven it was designed for... but nobody takes it seriously here.... So, I have great pizza off a plate that weighs a fraction of a steel plate, is designed for this use and works incredibly well.

By the way, one of my hobbies is adapting commercial recipes/formulations, ingredients, and equipment to home use.

A way for this plate to gain the respect of the community is to sucessfully attempt back-to-back pizzas & prove it will either recover very quickly or maintain adequate heat via thermal mass. The latter is likely already busted due to information we already know, so what you're really trying to prove is that the plate will recover & maintain heat better than plain steel due to the aluminum coating.

I like experiements, and the only way to prove it, well, is to prove it.

Actually, maybe I didn't state that previously, I had several posts deleted while trying to upload the photos until I found the problem on my end. Didn't copy paste until I lost 2 entries. Ok, I know better.

I for one do not doubt anything you say about the way your plate performs. I'm sure it does everything you say and is producing great pizza(I know it is you've posted some pictures). To me I just don't see anything magical here. Your experiences to this point are pretty much in line with what I would expect for steel. I personally don't think the thin aluminum coating has any effect on the thermal properties, it just offers a nice non reactive surface for the plate that commercial users would expect.

If you want to drastically oversimplify things like that, then yes as a matter of fact with my current setup I have preheated my 1/2" steel to over 700F in 10 minutes. But it doesn't work like that. For one most people are using 1/2" steel with nearly twice the thermal mass of your plate, meaning it will have nearly twice the preheat time. Second, every oven is different. I know you have tried multiple ovens with good results, but if the standard gas ovens you have used it with are out performing your commercial quality convection oven I am going to guess they just so happened to be pretty powerful ovens and lead to a fast preheat. I would guarantee some of the anemic ovens many users here have would not give the same results.

Understand I'd love to be wrong here, I'd love for there to be an even better material out there. There is just no theoretical reason for this material to be better then standard steel, and there I have not personally seen anything posted in this thread that changes that. That all said I am curious to see and hear about anything you can do to change my mind because I truly would love to be wrong about this one.

I don't know if this is mitigated to any extent because aluminized steel reflects 80% of radiant heat. This AK Steel product is also relativly thin compared to a pizza steel, and I don't know if that causes a meaningful difference. I would think that the thicker the Al is relative to the steel, the greater the impact on thermal conductivity, but I don't know.

I think this does suggest it's worth taking a closer look. There may be something to this.

CL

Logged

"We make great pizza, with sourdough when we can, commercial yeast when we must, but always great pizza." Craig's Neapolitan Garage

scott123

It shows the thermal conductivity of aluminized low-carbon steel to be 89 W/m°C at 20 °C

Prior to hearing this, I would have bet just about any amount of money that aluminized steel had the same thermal conductivity as regular steel. I'm glad I didn't In that sense, I do stand corrected.

Looking at the bigger picture, though, while 89 is almost 40% larger than 64, compared to cordierite (3ish) and aluminum (205), the difference is not that drastic. There's also the question of the aluminum to steel ratio and it's impact on conductivity that you brought up. At .015" (the smallest thickness they offer), if that's what they're using to calculate the 89 W/m°C number, then I have no doubt that as the thickness increases and the ratio of aluminum to steel decreases, the conductivity will decrease as well. Even if they're testing the conductivity using their greatest thickness, .14", it's not the .2" of the cadco.

Regardless of what the final conductivity figure clocks in at, bake times are a component of thermal conductivity and mass. .2" of aluminized steel isn't going to outperform 1/2" of steel, even with increased conductivity.

I'm still skeptical, but, I'll concede that the difference in conductivity is sufficient to warrant further investigation.

Ron, if you really want to test this, get your hands on some steel. I'm not sure if 1/5" steel can be easily found. If you can't get 1/5", get 1/4". If you really want to go crazy, buy an 8 x 16 steel plate, cut your cadco plate down to that size as well, combine the two side by side in the oven and bake a pizza, on both, at the same time. Or... if you don't want to carve up the cadco, just bake a pizza using the cadco, then, bake another pizza, at another time, using the steel, repeating every step carefully.

That is very interesting Craig, but Scott does bring up an interesting point. A thin aluminum coating would have an impact on the thermal properties of 24 gauge steel, but would have much less of an impact on 1/2" steel where it would make up a much smaller component of the thermal mass. Aluminized steel is commonly used in thin sheets for mufflers, ovens, and other high temperature parts. Considering the thermal conductivity number will not be static due to this, I would bet that number is indicative of it's common usage in the form of thin sheet, and not plate.

I guess we'll have to keep digging to get to the bottom of this and see if there is any other info about the thermal conductivity that specifies thickness.